Improvement in devices for the manufacture of drain-pipes



JOHN W.1STOCKWEL!-{ Improvement in Devices for the Manufacture of Drain Pipe.

Patented March19,l872.

Inventor.

Witnesses.

NITEID STATES JOHN w. STOOKWELL, or PORTLAND, MAINE.

tion of the same, reference being had to the accompanying drawing, which is made a part of this specification, in which----.

Figure 1 shows a side view in perspective of my invention; Fig. 2, top-edge view of the same with the latch in the first notch. Fig. 3

is an edge or end view with the latch in the second notch and the core contracted. Fig. 4. is a view of the rod for disengaging the latches within Fig. 1. Fig. 5 is a viewer part of the interior of Fig. 1 to show the latch or fastening more plainly. Fig. 6 is an end edge view of the two overlapping edges of the core, and thepiece of metal from which the lip f is formed. Fig. 7 is the same, showing the lip f, and with the core so contracted that the latch b may be placed over the further edge of the catch d.

Same letters show like parts.

My invention relates to a new and improved core, to be used in the manufacture of cement, drain, and water pipe. It refers to an elastic or expansible-and-contracting core, with certain devices connected therewith so as to facilitate the disengagement and removal of the core from the fresh or green pipe when just molded or after the material is set. To this end I make a hollow sheet-metal core, and then apply to its inner periphery the latches seen in Figs. 1

and 5. A strip. of metal, a, is fastened to the inside of the core near the upper end of the same, and a similar piece at the lower end. It is held by two rivets, and has a third rivet passing-through it, which serves as a pivot for the curved latch b. This latch 11 has a turnedup lip or end, 0, to hold the latch in place, and also to sustain-the strain when the core is held contracted or expanded by the said latch. One manner of using the said core is to have the sheet metal comprising it so rolled or bent up that, by its natural elasticity, itwould carry the lip 0 over the edge 61 of the catch; but, when prepared for use in the outer case, which contains the cement, the core is so expanded as to allow the latch b to enter the slot 6. This Specification forming part of Letters Patent No. 124,702, dated March 19, 1872.

I keeps the core inthe desired condition of expansion. The core may, however, be bent and used so that its natural position, by reason of its elasticity, would fill the entire ap erature or core of the joint of pipe. In this case, inasmuch as the core projects somewhat above the top of the newly-made piece of pipe, it can be contracted by hand or some convenient device, and then held thus contracted by the latches b passing over the catch. In either case the elastic core is, when the pipe is being made or when the material is being filled in around the core, held expanded and kept firm and rigid, so to speak, by the latches I), placed both near the top and bottom ends of the core on its interior and, when the pipe is completed and. the core to be removed, the latches are lifted and the core, either byits own elasticity or by force applied, contracted to a smaller diameter, so as to be disengaged from the inside or sides of the core or pipe then in this condition also held by the latches b, and then lifted out of the joint of pipe. The two edges of the pieces of metal forming the core overlap, as seen in Fig. 6, the inner one being bent to pass under the outer edge and keep the exterior surface of the core smooth, so as not'to make a seam in the inside of the pipe.

f is a lip projecting inward from the top edge of the core, and formed on a small piece of metal (f, Fig. 6) riveted to the inside of the outer of the two overlapping edges of the metal sheet composing the core. The purpose of this is to keep the top edge of the core even, and to prevent one of the overlapping edges of the metal from rising or working above the other, and so in time giving a twist to the core.

'11 is a slat, of the form shown in Fig. 1, to fasten and hold down the core in place on the bottom-former, which may be furnished with a small stud for the purpose, so that, the core being placed in position and the stud slipping up into the vertical part of the slot, a slight turn of the core will move the horizontal part of the slot over the stud and thus hold the core in place.

m, Fig. 4, shows the hook with its handle 7 to reach down into the core and unlatch the.

lower latch when a joint of pipe is made and the core is about to be contracted preparatory the, latches b, piece a, catch (1, lips f and c,

and slot 6, as herein set forth.

2. In combination with the core, made as described, I claim the hook m n, as and for the purpose set forth.

J OHN W. STOCKWELL.

Witnesses WILLIAM HENRY CLIFFORD, D, W. SORIBNER. 

